1. Field of the Invention
The present invention relates to a vehicle safety device provided on a hood which covers an engine room at a frontal part of a vehicle.
2. Description of the Related Art
Recent developments in automotive technology provide arrangements for lifting a hood of a vehicle covering an engine room in the event of a collision of a vehicle with an obstacle so that the raised hood would receive the obstacle and mitigate an impact acting on the obstacle in the collision (refer to Japanese Unexamined Patent Publication Nos. 2002-37125 and 2003-89362).
An arrangement described in Japanese Unexamined Patent Publication No. 2003-89362 is such that a motor 1 turns when a control signal is fed from a control unit and, as a consequence, a movable plate 2 moves rearward and a link 3 connected to the movable plate 2 goes into an upright position in an interlocked fashion, whereby a rear part of a hood connected to the link 3 via a bracket 4 is lifted as shown in FIG. 22.
An arrangement described in Japanese Unexamined Patent Publication No. 2002-37125 includes a pair of links 5 connected to each other and a first actuator 8, one of the links 5 being joined to a bracket 6 which is fixed to a hood and the other being joined to a vehicle body 7. When a collision with an obstacle is detected, the first actuator 8 extends and the links 5 which have been folded become extended, whereby the hood is lifted as shown in FIG. 23.
If the hood of a vehicle provided with this kind of vehicle safety device is lifted as a result of activation thereof caused by too sensitive detection of an obstacle, for example, a driver must lower the hood which has been lifted to obtain an unobstructed forward view and drive the vehicle to a nearest repair shop or like facility.
In the aforementioned vehicle safety device of Japanese Unexamined Patent Publication No. 2003-89362, the motor 1 is run in a reverse direction to bring the link 3 which has been erected to the upright position back to a generally horizontal position in order thereby to lower the hood. In the aforementioned vehicle safety device of Japanese Unexamined Patent Publication No. 2002-37125, on the other hand, a second actuator 9 pulls a wire 10 to fold back the links 5 which have been extended in order thereby to lower the hood.
The vehicle safety devices of the prior art require the motor 1 which is rather expensive or the dedicated second actuator 9 (besides the first actuator 8) for lowering the hood which has been lifted as seen above. These prior art arrangements would inevitably entail higher cost or system complication. Moreover, the prior art arrangements require a space for installing the motor 1 or the second actuator 9, so that the safety device increases in size and a site for installation thereof is limited.